Admitted mobster back behind bars, accused of murder

When last we checked in with convicted mobster, FBI informant and accused scammer Chulpayev, he wasn't saying much.

"If you put me on TV, I will sue the (expletive) out of your company," he told WSB-TV in February.

Norman Simmons, a Houston rapper and business owner, was accusing Chulpayev of selling very expensive cars Chulpayev didn't own. When ABC's Brian Ross tracked Chulpayev down, he denied it all.

"And these allegations from Atlanta and Houston?" Ross asked Chulpayev.

"Are fake. Completely," he said.

"All of them?" Ross pressed.

"All of them."

The Houston case is still pending, but now Chulpayev has bigger problems.

Chulpayev is in an Atlanta jail, charged with four others in the killing of a rapper and car customer who was apparently about to testify against Chulpayev over a bad car deal. He denies any involvement in this crime, too.

"He's in a lot of trouble," Ross said.

Chulpayev is a convicted arsonist and extortionist going back to his days running numbers for the Russian mob New York in the late 90's. Sentences for those crimes were reduced after he cooperated with the FBI. But now Chulpayev says he kept cooperating with the FBI and is making explosive claims about his FBI handler.

"Chulpayev is now telling everybody that he paid off the FBI agent -- gave him gifts and cash to keep him out of trouble. And that is an allegation the FBI is now taking very seriously," Ross said.

It may finally be the unraveling of Chulpayev's tangled web.

"I'm just smarter than you and that's it. I am an average guy that thinks ahead. And that's what it is. People can't stand it. Stupid people can't stand it. Smart people, they work with me," Chulpayev said.

"I think he's not quite as smart as he thinks," Ross said.

Ross tells us the FBI is investigating Chulpayev's claims. If he's convicted in the Atlanta murder, it could mean his alleged Houston victim will never see Chulpayev in court.